Accession Number : AD0738316

Title :   Noise in the Neutral Sheet in the Geomagnetic Tail.

Descriptive Note : Final scientific rept. 1 Dec 70-30 Nov 71,

Corporate Author : IMPERIAL COLL OF SCIENCE AND TECHNOLOGY LONDON (ENGLAND) DEPT OF PHYSICS

Personal Author(s) : Dungey,James W.

Report Date : JAN 1972

Pagination or Media Count : 18

Abstract : An instability which could cause noise in the neutral sheet is proposed. The starting point is the self-consistent model of the undisturbed sheet developed in the absence of a normal component of magnetic field by Cowley. In this steady state the electrons trapped in the field reversal region move across the tail from dusk to dawn, undergoing acceleration in the cross tail electric field at the dusk end. After emerging from the acceleration region only ions in this region are relatively cold. The authors found that a wave propagating at an angle to the normal of the current sheet can be unstable due to a double jump in the velocity distribution. Resonating electrons give energy to the wave, while the wave energy probably leads to heating of the cold ion background. (Author)

Descriptors :   (*MAGNETOSPHERE, NOISE(RADIO)), STABILITY, GEOMAGNETISM, OSCILLATION, PLASMAS(PHYSICS), ELECTRON DENSITY, DISTRIBUTION FUNCTIONS, GREAT BRITAIN

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE